Soil Preparation for Garlic Bulbs
Preparing the soil prior to planting is a step many gardeners skip to save time and effort, but your garlic’s health and growth depend upon fertile, well-drained soil. Always test your soil before planting to determine whether or not it’s deficient in any essential nutrients and/or minerals and to determine the pH of the soil. It’s easy to do a soil test yourself with one of our digital meters, or to have a test done by your local County Extension office.
The other goal of soil preparation is to loosen compacted soil and make it friable (crumbly and aerated) so water can properly drain away from your plants.
NOTE: This is part 5 in a series of 9 articles. For a complete background on how to grow garlic bulbs, we recommend starting from the beginning.
When To Prepare Your Soil
Soil preparation can be done any time the ground is not too wet, or frozen. Your garlic can be planted even when temperatures are quite cool. Generally, as long as your soil is workable, it is fine to plant—but before you do, make sure your soil is the best it can be.
Soil Types
Know your soil! All areas of the country are different, even from township to township. Identify your soil type and amend it as needed. Garlic grows best in a loam or sandy loam soil.
Clay and silt soils are made of very small particles. They feel slick and sticky when wet. Clay and silt hold moisture well, but resist water infiltration, especially when they are dry. Often, puddles form on clay or silt soils and they easily become compacted.
Loam is a mix of sand, silt or clay, and organic matter. Loam soils are loose and look rich. When squeezed in your fist, moist loam will form a ball, which crumbles when poked with a finger. Loam soils normally absorb water and store moisture well. Loam soils can be sandy or clay-based, and will vary accordingly in moisture absorption and retention.
Sandy soils contain large particles that are visible to the unaided eye, and are usually light in color. Sand feels coarse when wet or dry, and will not form a ball when squeezed in your fist. Sandy soils stay loose and allow moisture to penetrate easily, but do not retain it for long-term use.
If your soil is so poor that it’s beyond amending, you can always create a raised bed. It can be any shape you like as long as it’s large enough to contain the number of garlic bulbs you want to plant. The bed should be at least 8 inches deep.
You can even plant garlic in a container (use at least a 1-gallon size or larger) and locate the pot where it will receive sun exposure 6-8 hours each day.
Soil pH
It’s also good to know whether your soil is acidic (pH below 7.0) or alkaline (pH above 7.0). Garlic prefers soil with a pH between 6.0 and 7.0. Your local county extension service can perform a soil test for you, or you can use one of our digital soil pH meters. If your soil is too acidic, mix in ground limestone; if it’s too alkaline, add peat moss.
How To Prepare Your Soil
Roots will grow faster when they have ample space, and a larger root system means a bigger garlic bulb! After you have amended the soil pH and/or any nutrient/mineral deficiencies (if needed), prepare the area in which you want to grow your garlic by removing the soil to a depth of at least 8".
To loosen the pile of soil you’ve dug out, mix composted cow manure, garden compost or peat moss (up to 1/3 concentration) into your excavated soil. Make sure the peat moss you get is either baled sphagnum or granular peat. You can also add our Coco-Fiber Potting Medium or 2 or more inches of organic material and evenly work it into your soil. Organic materials bind sandy soil particles so they retain moisture and nutrients better. They also break apart clay and silt particles, so that water can infiltrate and roots can spread.
Your lawn can provide you with ideal organic materials such as grass clippings (not treated with herbicides) and shredded leaves. Not only will the grass and leaves break down to provide soil nutrients, but they will help loosen the soil as well. You can gather these in the fall with spring planting in mind.
Common soil amendments: * Compost * Sand * Composted manure * Lime * Peat moss (either baled sphagnum or granular peat)
Fertilizer First!
Garlic grows best when fertilizer is added into the planting hole before planting, vs. being sprinkled on top of the soil after planting.
After you amend the soil and dig your trench/patch, evenly sprinkle 1/2 cup of balanced fertilizer that is slightly nitrogen-heavy for every 10 linear feet of soil. (Nitrogen is the first number on the fertilizer package. Choose a brand with a first number that’s higher than the other two, like 15-10-5 or 20-10-10.)
Add back enough soil to create the correct planting depth (as described in the How Deep To Plant section of the Planting article).
Once your soil is properly prepared, you are ready to plant!
